Using supercritical fluids to refine hydrocarbons

Abstract

A system and method for reactively refining hydrocarbons, such as heavy oils with API gravities of less than 20 degrees and bitumen-like hydrocarbons with viscosities greater than 1000 cp at standard temperature and pressure, using a selected fluid at supercritical conditions. A reaction portion of the system and method delivers lightweight, volatile hydrocarbons to an associated contacting unit which operates in mixed subcritical / supercritical or supercritical modes. Using thermal diffusion, multiphase contact, or a momentum generating pressure gradient, the contacting unit separates the reaction products into portions that are viable for use or sale without further conventional refining and hydro-processing techniques.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation-in-part of, and claims priority to, co-pending U.S. patent application Ser. No. 12 / 978,294 filed on 23 Dec. 2010, entitled “Using Supercritical Fluids to Refine Hydrocarbons,” the entirety of which is incorporated herein by reference.STATEMENT REGARDING FEDERALLY SPONSORED R&D[0002]This invention was made with Government support under Contract No. DE-AC52-06NA25396 awarded by the U.S. Department of Energy to Los Alamos National Security for the management and operation of the Los Alamos National Laboratory. The Government has certain rights in this invention.BACKGROUND OF THE INVENTION[0003]1. Field of the Invention[0004]The present invention relates to using a supercritical fluid, typically water, with or without additives such as inorganic salts such as NaOH or KOH which increase the pH and the subsequent solvent capacity, selected hydrocarbons, or other soluble elements or compounds such as oxygen, ai...

AI Technical Summary

Benefits of technology

The patent describes a system and method for upgrading heavy oils and bitumen-like hydrocarbons using a supercritical fluid. The supercritical fluid efficiently dissolves and extracts the heavy oil from a porous solid, and then thermally splits the higher molecular weight hydrocarbons to lighter, more volatile hydrocarbons. The system includes a reactor portion and a mix of the supercritical fluid and additives to promote the thermal cracking process. The method improves the safety of process operators by reducing processing complexity and eliminating combustible and hazardous reagents.

Problems solved by technology

World oil supply is changing, and the readily available medium to light crude oil reserves are getting harder to find and develop.

Known techniques require complex, expensive equipment and an involved refinery infrastructure that includes capacity to produce hydrogen, heating fuel and maintain equipment and supplies.

In addition, the process does not provide a method for handling the unreacted portion of the feed, or a means to control the reaction so that the product distribution can be controlled.

This method is limited to working with heavy hydrocarbons in-situ, and the efficiency of the method is dependent on the reservoir conditions and physical properties.

It would be difficult to ensure that optimal conditions are maintained to get the best product distribution.

In addition, the process requires additional means to inject oxidizing gases and recover the combustion gases that contribute to the carbon footprint of the process.

However, the publication does not describe means to control the product distribution or quality, nor means to deal with unreacted heavy hydrocarbons.

The method is limited by the formation of solid carbonaceous materials that necessitate the shutdown and clean out of the reactor.

The multi-pass portion required to effect the necessary mixing also limits the means to effectively clean and maintain the contacting device.

In addition, the heating profile described is complex and requires shortened heat-up times between the heating stages to reduce coke formation.

This limits the operating time and potential throughput of the method.

This method, however, is limited by using a solvating hydrocarbon to essentially dissolve and then react with the heavy hydrocarbons.

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